Linked Questions
46 questions linked to/from How do non-conservative forces affect Lagrange equations?
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Lagrangian formalism and dissipative systems [duplicate]
Why the central concepts of classical mechanics, viz. Lagrangian and Hamiltonian formalisms cannot address constraint forces like friction and others in dissipative systems?
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Which class of Dynamical Systems is governed by Lagrangian Dynamics? [duplicate]
Lagrangian formalism is a technique using which we can obtain the time evolution of a dynamical system. Given a dynamical system, can we say whether or not we can write down a Lagrangian (solving it ...
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Systems that Satisfy the Euler–Lagrange equations, and Velocity dependent vs Dissipative forces [duplicate]
"if the force is not derived from a potential, then the system is said to be polygenic and the principle of least action, that the action integral $S$ is stationary at the actual path followed is ...
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What are holonomic and non-holonomic constraints?
I was reading Herbert Goldstein's Classical Mechanics. Its first chapter explains holonomic and non-holonomic constraints, but I still don’t understand the underlying concept. Can anyone explain it to ...
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How do I show that there exists variational/action principle for a given classical system?
We see variational principles coming into play in different places such as Classical Mechanics (Hamilton's principle which gives rise to the Euler-Lagrange equations), Optics (in the form of Fermat's ...
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Lagrangian and Hamiltonian EOM with dissipative force
I am trying to write the Lagrangian and Hamiltonian for the forced Harmonic oscillator before quantizing it to get to the quantum picture. For EOM $$m\ddot{q}+\beta\dot{q}+kq=f(t),$$ I write the ...
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What causes a force field to be "non-conservative?"
A conservative force field is one in which all that matters is that a particle goes from point A to point B. The time (or otherwise) path involved makes no difference.
Most force fields in physics ...
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Euler-Lagrange equations with non-conservative force (example)
I am trying to understand how to use the Euler-Lagrange formulation when my system is subject to external forces. Consider the system pictured below:
Let's define the lagrangian, as always, as $L =...
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Connection between different kinds of "Lagrangian"
Being a physic student I first heard the term: "Lagrangian" during a course about Lagrangian mechanics; at that time this term was defined to me in the following way:
For a classic, non ...
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Generalized definitions of Lagrangian and Hamiltonian functions
When we enter into the scope of Analytical mechanics we usually start with these two primary notions: Lagrangian function & Hamiltonian function
And usually textbooks define Lagrangian as $L=T-V$ ...
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The Role of Friction in The Lagrangian
I'm pretty new to physics (I am presently taking AP Physics 1 though I am far ahead of that in math) and I was reading this paper that found the equations of motion for Atwood's machine using ...
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The Equivalency of Newton's Second Law, Hamilton's Principle and Lagrange Equations [closed]
Consider the following question in classical mechanics
Are Newton's Second Law, Hamilton's Principle and Lagrange Equations equivalent
for particles and system of particles?
If Yes, where ...
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How do I include friction due to normal force in Lagrange Equations?
I am going through the Goldstein book on classical mechanics and the after he derived the Lagrange equations he used Rayleigh dissipation function to include friction as a generalized force. In school ...
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Problems that Lagranges equations of the 1st kind can solve whereas the 2nd kind can't?
Can anyone give examples of mechanics problems which can be solved by Lagrange equations of the first kind, but not the second kind?
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Lagrangian Mechanics, When to Use Lagrange Multipliers?
I've seen a few other threads on here inquiring about what is the point of Lagrange Multipliers, or the like. My main question though is, how can I tell by looking at a system in a problem that ...